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                                                                   EXHIBIT 10.15

                                    AGREEMENT

This AGREEMENT is made and entered into February 6, 2003 (this "Agreement") by
and between Arbinet-thexchange, Inc. (formerly known as Arbinet Holdings, Inc. a
Delaware corporation, the "Company") having an office at 75 Broad Street, 20th
Floor, New York, NY 10004 and Anthony L. Craig, an individual currently residing
at 4041 Arrow Wood Court, Bonita Springs, FL 34134 (collectively, the
"Parties").

WHEREAS, the Company and Mr. Craig entered into that certain employment
agreement dated December 2nd 1999 as amended by that certain Letter Agreement
dated as of August 3, 2000 and further amended by the Amended and Restated
Employment Agreement dated February 12th 2001 (the "Prior Agreement").

WHEREAS, the Company and Mr. Craig desire to replace and supersede the Prior
Agreement on the terms set forth herein.

WHEREAS, Mr. Craig entered into those certain promissory notes dated February
28, 2000 and March 6, 2001 in favor of the Company and has agreed to amend the
terms of these promissory notes (the "Loan Agreements").

WHEREAS, the Board of Directors (the "Board") elected Mr. Craig as the Chairman
of its Board of Directors on August 2, 2000. On October 17, 2001, the Board
elected to remove the word "Executive" from his title, in light of the
Mr. Craig's acceptance as President and CEO of Safeguard Scientifics.

NOW THEREFORE, in consideration of the mutual covenants hereinafter contained,
the Parties agree as follows:

1.      Termination of Prior Agreement. The Parties agree the Prior Agreement
        was terminated as of October 31, 2001 (the "Employment Termination
        Date"), and Mr. Craig agrees to and has provided services under the
        terms described herein since the Employment Termination Date.

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2.      Services.

        a.      Position. The Company hereby retains Mr. Craig to perform
                business consulting services as Chairman of the Company's Board
                of Directors, and Mr. Craig agrees to perform such services for
                the Company on the terms and conditions hereinafter set forth,
                for so long as Mr. Craig remains Chairman of the Company.
                Chairman shall have such authority and shall perform such duties
                and responsibilities as are set forth in the Company's by-laws,
                are delegated by the Company's Board of Directors and are
                ordinary or necessary to the position of Chairman of the Board.

        b.      Independent Contractor. In accordance with the mutual intentions
                of the Company and Mr. Craig, this Agreement establishes between
                them an independent contractor relationship, and all of the
                terms and conditions of this Agreement shall be interpreted in
                light of that relationship. Mr. Craig agrees to furnish personal
                services as provided in this Agreement as an independent
                contractor using Mr. Craig's own means and methods. Mr. Craig is
                engaged in an advisory capacity. There is no intention to create
                by this Agreement an employer-employee or agency relationship.

3.      Term. Mr. Craig shall provide services under the terms of this Agreement
        until Mr. Craig's services are terminated pursuant to Paragraph 7 below.

4.      Fees. Mr. Craig shall be paid a fee of Six Thousand Two Hundred Fifty
        Dollars ($6,250) on the last day of each calendar month in which he
        performs services under this Agreement. The fees provided for under the
        terms of this paragraph shall constitute full payment for Mr. Craig's
        services to the Company under this Agreement, and Mr. Craig shall not
        receive any additional payments for his services. Mr. Craig agrees to
        accept exclusive liability for the payment of all taxes and
        contributions owing in either a personal or professional capacity on, or
        arising out of, any of the payments made to Mr. Craig under this
        Agreement and the Loan Agreements with the Company and to reimburse and
        indemnify the Company for such taxes or contributions or penalties that
        the Company may be compelled to pay in the event that Mr. Craig fails to
        pay such taxes

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        or contributions. Mr. Craig also agrees to comply with all valid
        administrative regulations respecting the assumption of liability for
        such taxes and contributions.

5.      Business Expenses. Mr. Craig shall be reimbursed for all reasonable
        expenses for travel and entertainment, provided Mr. Craig shall account
        for and substantiate all such expenses in accordance with Company
        policies and guidelines.

6.      Freedom to Contract. Mr. Craig represents and warrants that he has the
        right to enter into this Agreement, that he is eligible to perform the
        services provided for hereunder for the Company and that no other
        written or verbal agreements exist that would be in conflict with or
        prevent performance of any portion of this Agreement. Mr. Craig further
        agrees to hold the Company harmless from any and all liability arising
        out of any prior contractual obligations entered into by Mr. Craig. Mr.
        Craig represents and warrants that he has not made and will not make any
        contractual or other commitments that would conflict with or prevent his
        performance of any portion of this Agreement or conflict with the full
        enjoyment by the Company of the rights herein granted.

7.      Termination, Notwithstanding the provisions of Paragraph 3 above, Mr.
        Craig's services under this Agreement shall be terminated on the
        earliest of the following dates:

        a.      Death. On the date of Mr. Craig's death.

        b.      By Notice. On the date that Mr. Craig notifies Company in
                writing that he wishes to terminate his services under this
                Agreement.

        c.      By the Board. On the date that the Company's Board of Directors
                notifies Mr. Craig in writing of the date of termination of his
                services as Chairman of the Board for any or no reason.

        Following the termination of Mr. Craig's services under this Agreement,
        the Company will have no further liability to Mr. Craig and no further
        payments will be made to Mr. Craig, except: (i) the Company shall pay to
        Mr. Craig (or, in the case of automatic termination upon Mr. Craig's
        death under subparagraph (a) above, to Mr. Craig's legal representatives
        or such named beneficiaries as Mr. Craig may designate from time to time
        in a writing delivered to the Company) the pro rata portion of his
        monthly fee for the

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        relevant calendar month through the date of termination, calculated by
        multiplying the Six Thousand Two Hundred Fifty Dollar ($6,250) fee by a
        fraction, the numerator of which will be the number of days in the
        calendar month of termination prior to termination and the denominator
        of which shall be the number of days of that month; and (ii) to the
        extent Mr. Craig is entitled to the reimbursement of business expenses
        incurred prior to termination as provided in Paragraph 5 above.

8.      Restrictive Covenants.

        a.      Confidentiality. Mr. Craig agrees that both during the term of
                this Agreement and thereafter he will not disclose to any third
                party or use in any way (except in furtherance of the best
                interests of the Company during his performance of services
                hereunder during the Agreement's term) any proprietary
                information or confidential records, including without
                limitation (i) the software products, programs, applications and
                processes utilized by the Company (other than prepackaged "off
                the shelf" products); (ii) the name and/or address of any
                customer or affiliate of the Company or any information
                concerning the transactions or relations of any customer, vendor
                or affiliates of the Company with the Company or any of its
                partners, principals, stockholders, directors, officers or
                agents; (iii) any information concerning any product,
                technology, or procedure employed by the Company but not
                generally known to its customers, vendors or competitors, or
                under development by or being tested by the Company but not at
                the time offered by the Company generally to customers or
                vendors; (iv) any information relating to the Company's computer
                software, computer systems, pricing or marketing methods, sales
                margins, cost of goods, cost of material, capital structure,
                operating results, borrowing arrangements or business plans; (v)
                any information which is generally regarded as confidential or
                proprietary in any line of business engaged in by the Company;
                (vi) any business plans, budgets, advertising or marketing
                plans; (vii) any information contained in any of the Company's
                written or oral policies and procedures or manuals; (viii) any
                information belonging to customers, vendors or affiliates of the
                Company or any other person or entity that the Company has
                agreed to hold in confidence; (ix) any inventions, innovations
                or improvements covered by this Agreement; and (x) all written,
                graphic and other material relating

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                to any of the foregoing. Mr. Craig acknowledges and understands
                that information that is not novel or copyrighted or patented
                may nonetheless be proprietary information. The term
                "proprietary information" shall not include information
                generally available to the public or information that is or
                becomes available to Mr. Craig on a non-confidential basis from
                a source other than the Company or the Company's directors,
                officers, employees, partners, principals or agents (other than
                as a result of a breach of any obligation of confidentiality).
                Immediately upon termination of Mr. Craig's services under this
                Agreement or at any other time upon the Company's request, Mr.
                Craig will return to the Company all personal property
                (including without limitation, all files, records, documents,
                lists, equipment, supplies, promotional materials, keys, phone
                or credit cards and similar items and all copies thereof or
                extracts therefrom) and confidential records of the Company. For
                purposes of this Agreement, "confidential records" means all
                correspondence, memoranda, files, manuals, books, lists,
                financial, operating or marketing records, magnetic tape, or
                electronic or other media or equipment of any kind.

        b.      No Solicitation of Employees. Mr. Craig agrees that, both during
                the term of this Agreement and for a period of twelve (12)
                months following the termination of Mr. Craig's services under
                this Agreement at any time and for any reason, Mr. Craig will
                not, on behalf of himself or any other person or entity directly
                or indirectly solicit or attempt to solicit (i) any of the
                employees (other than clerical or non-administrative employees),
                agents, consultants or representatives of the Company to
                terminate his, her or its relationship with the Company; or (ii)
                any of the employees, agents, consultants or representatives of
                the Company to become employees, agents, representatives or
                consultants of any other person or entity (including Mr. Craig
                or any person or entity owned or controlled by Mr. Craig).

        c.      No Solicitation of Customers. Vendors and Distributors. Mr.
                Craig agrees that, both during the term of this Agreement and
                for a period of twelve (12) months following the termination of
                this Agreement at any time and for any reason, Mr. Craig will
                not, on behalf of himself or any other person or entity,
                directly or indirectly solicit or attempt to solicit any
                customer, vendor or distributor of the Company with respect to
                any product or service (i) being furnished, made, sold or

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                leased by the Company, or (ii) proposed to be furnished, made,
                sold or leased by the Company and which is covered in a written
                proposal or business plan by the Company.

        d.      Non-Competition. During the term of this Agreement and for a
                period of twelve (12) months following the termination of Mr.
                Craig's services under this Agreement at any time and for any
                reason, Mr. Craig shall not, on behalf of himself or any other
                person or entity, directly or indirectly (whether as officer,
                director, employee, consultant, investor, lender, joint
                venturer, partner, stockholder, sole proprietor or otherwise),
                be employed by, perform any services for or hold any ownership
                interest in any business in competition with any business
                conducted by the Company or its affiliates in any jurisdiction
                where the Company and/or its affiliates conduct such business as
                of the date of the termination of Mr. Craig's services hereunder
                (including, without limitation, any business activity or
                jurisdiction which is covered by or included in a written
                proposal or business plan existing as of the date of the
                termination of Mr. Craig's services hereunder). The above
                notwithstanding, it shall not be considered a violation of this
                subparagraph (d) if Mr. Craig (i) owns, for investment purposes,
                up to one percent (1%) of the total outstanding equity
                securities of a publicly traded company, and/or (ii) performs
                services for any enterprise to the extent such services are not
                performed, directly or indirectly, for a business unit of the
                enterprise in competition with the Company and/or its
                affiliates. The Company does not anticipate that Mr. Craig's
                position as Chief Executive Officer with Safeguard Scientifics,
                Inc., as that company's business is currently constituted, will
                violate this restrictive covenant.

        e.      Enforcement. Mr. Craig acknowledges and agrees that the
                Company's business is of a highly competitive nature and that
                the services to be provided by Mr. Craig under this Agreement
                are of a special, unique and extraordinary nature. Mr. Craig
                further acknowledges and agrees that the restrictions contained
                in this Paragraph 8 are necessary to prevent the use and
                disclosure of confidential information and to protect other
                legitimate business interests of the Company. Mr. Craig
                acknowledges that all of the restrictions in this Paragraph 8
                are reasonable in all

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                respects, including duration, territory and scope of activity.
                Mr. Craig agrees that the restrictions contained in this
                Paragraph 8 shall be construed as separate agreements
                independent of any other provision of this Agreement or any
                other agreement between Mr. Craig and the Company. Mr. Craig
                agrees that the existence of any claim or cause of action by Mr.
                Craig against the Company, whether predicated on this Agreement
                or otherwise, shall not constitute a defense to the enforcement
                by the Company of the covenants and restrictions in this
                Paragraph 8. Mr. Craig agrees that the restrictive covenants
                contained in this Paragraph 8 are a material part of Mr. Craig's
                obligations under this Agreement for which the Company has
                agreed to compensate Mr. Craig as provided in this Agreement.
                Mr. Craig agrees that the injury the Company will suffer in the
                event of the breach by Mr. Craig of any clause of this Paragraph
                8 will cause the Company irreparable injury that cannot be
                adequately compensated by monetary damages alone. Therefore, Mr.
                Craig agrees that the Company, without limiting any other legal
                or equitable remedies available to it, shall be entitled to
                obtain equitable relief by injunction or otherwise from any
                court of competent jurisdiction, including, without limitation,
                injunctive relief to prevent Mr. Craig's failure to comply with
                the terms and conditions of this Paragraph 8. The twelve (12)
                month periods referenced in subparagraphs (b), (c) and (d) above
                shall be extended on a day-for-day basis for each day during
                which Mr. Craig violates the provisions of subparagraphs (b),
                (c) or (d) in any respect, so that Mr. Craig is restricted from
                engaging in the activities prohibited by subparagraphs (b), (c)
                and (d) for the full twelve (12) month period.

9.      Intangible Property. Mr. Craig will not at any time during or after the
        term of this Agreement have or claim any right, title or interest in any
        trade name, trademark, patent, copyright, work for hire or other similar
        rights belonging to or used by the Company and shall not have or claim
        any right, title or interest in any material or matter of any sort
        prepared for or used in connection with the business or promotion of the
        Company, whatever Mr. Craig's involvement with such matters may have
        been, and whether procured, produced, prepared, or published in whole
        or in part by Mr. Craig, it being the intention of the Parties that Mr.
        Craig shall and hereby does, recognize that the Company

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        now has and shall hereafter have and retain the sole and exclusive
        rights in any and all such trade names, trademarks, patents, copyrights
        (all of Mr. Craig's work in this regard being a work for hire for the
        Company under the copyright laws of the United States), material and
        matter as described above. If any such work created by Mr. Craig is not
        a work made for hire under the copyright laws of the United States, then
        Mr. Craig hereby assigns to the Company all right, title and interest in
        each such work (including without limitation all copyright rights). Mr.
        Craig will promptly disclose in writing to the Company any and all
        inventions, innovations, or improvements (including policies,
        procedures, products, improvements, software, ideas and discoveries)
        conceived or made by Mr. Craig, either alone or jointly with others. Mr.
        Craig shall cooperate fully with the Company during the term of this
        Agreement and thereafter in the securing of trade name, trademark,
        patent or copyright protection or other similar rights in the United
        States and in foreign countries and shall give evidence and testimony
        and execute and deliver to the Company all papers requested by it in
        connection therewith.

10.     Non-Disclosure. Except as may be required by law, neither Mr. Craig nor
        the Company shall disclose the financial terms of this Agreement to
        persons not involved in the operation of the Company, and the Parties
        shall disclose the financial terms of the Agreement to those involved in
        the operation of the Company only as needed to implement the terms of
        the Agreement or carry out the operations of the Company. The above
        notwithstanding, the financial terms of the Agreement may be disclosed
        to: (i) the Parties' attorneys, accountants, financial or tax advisors,
        and any potential investors in or purchasers of the Company, provided
        such persons agree not to disclose such terms of the Agreement further;
        and (ii) members of Mr. Craig's immediate family, provided such family
        members agree not to reveal the terms of the Agreement further.

11.     Successors and Assigns. The rights and obligations of the Company under
        this Agreement shall be binding on and inure to the benefit of the
        Company, its successors and permitted assigns. The rights and
        obligations of Mr. Craig under this Agreement shall be binding on and
        inure to the benefit of the heirs and legal representatives of Mr.
        Craig. Neither Party may assign this Agreement without the prior written
        consent of the other, except that the Company may assign the Agreement
        to any entity acquiring all or substantially all of the assets or the
        business of the Company.

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12.     Waiver or Modification. Any waiver by the Company of a breach of any
        provision of this Agreement shall not operate as, or be construed to be,
        a waiver of any other breach of such provision of this Agreement. The
        failure of the Company to insist on strict adherence to any term of this
        Agreement on one or more occasions shall not be considered a waiver or
        deprive the Company of the right thereafter to insist on strict
        adherence to that term or any other term of this Agreement. Neither this
        Agreement nor any part of it may be waived, changed or terminated
        orally, and any waiver, amendment or modification must be in writing
        signed by Mr. Craig and the Company's Chief Executive Officer.

13.     Counterparts. This Agreement may be executed in any number of
        counterparts, each of which shall, when executed, be deemed to be an
        original and all of which. shall be deemed to be one and the same
        instrument.

14.     Choice of Law. This Agreement will be governed and construed and
        enforced in accordance with the laws of the State of New York, without
        regard to its conflicts of law rules. Any action to enforce this
        Agreement must be brought in a court situated in the State of New York
        and the Parties hereby consent to the jurisdiction of courts situated in
        the State of New York.

15.     Entire Agreement. This Agreement contains the entire understanding of
        the Parties relating to the subject matter of this Agreement and
        supersedes all other prior written or oral agreements, understandings
        or arrangements between the Parties relating to the subject matter
        hereof, including, without limitation, the Prior Agreement. Mr. Craig
        agrees and acknowledges that he has been provided with everything to
        which he is entitled under the Prior Agreement, and that he will not
        receive any further payments or benefits thereunder. Mr. Craig
        acknowledges that, in entering into this Agreement, he does not rely and
        has not relied on any statements or representations not contained in
        this Agreement.

16.     Severability. Any term or provision of this Agreement that is
        determined to be invalid or unenforceable by any court of competent
        jurisdiction in any jurisdiction shall, as to such jurisdiction, be
        ineffective to the extent of such invalidity or unenforceability without
        rendering invalid or unenforceable the remaining terms and provisions of
        this Agreement

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        or affecting the validity or enforceability of any of the terms or
        provisions of this Agreement in any other jurisdiction and such invalid
        or unenforceable provision shall be modified by such court so that it is
        enforceable to the extent permitted by applicable law.

17.     Notices. All notices and other communications required or permitted to
        be given under this Agreement shall be in writing and delivery shall be
        deemed to have been made (i) three business days following the date
        when such notice is deposited in first class mail, postage prepaid,
        return receipt requested; or (ii) the business day following the date
        when such notice is deposited with any nationally reputable overnight
        air courier service to the Party entitled to receive the same, at the
        address indicated below or at such other address as such Party shall
        have specified by written notice to the other Party given in accordance
        with the terms of this Paragraph 17:

                If to the Company        Arbinet-thexchange Inc.
                                         75 Broad Street, 20th Floor
                                         New York, NY 10004
                                         Attention: Chief Executive Officer

                with a copy to:          Arbinet-thexchange, Inc.
                                         75 Broad Street, 20th Floor
                                         New York, NY 10004
                                         Attention: Contract Compliance

                If to Mr. Craig:         Anthony L. Craig
                                         4041 Arrow Wood Court
                                         Bonita Springs, FL 34134

18.     Headings. The headings of any paragraphs in this Agreement are for
        reference only and shall not be used in construing the terms of this
        Agreement.

19.     No Third Party Beneficiaries. This Agreement does not create, and shall
        not be construed as creating any rights enforceable by any person not a
        Party to this Agreement.

20.     Survival. The covenants, agreements, representations and warranties
        contained in this Agreement shall survive the termination of Mr. Craig's
        services under this Agreement at any time and for any reason.

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        IN WITNESS WHEREOF, this Agreement has been executed and delivered by
the Parties as of the first date written above.

                                              ARBINET-THEXCHANGE, INC.


                                              By   /s/ J. Curt Hockerneier
                                                --------------------------------
                                                   J. Curt Hockerneier
                                                   President & CEO


                                              ANTHONY L. CRAIG


                                                   /s/ Anthony L. Craig
                                                --------------------------------